Hu Ningjing, Luo Yongming, Wu Longhua, Song Jing
Soil and Environment Bioremediation Research Centre, State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China.
Int J Phytoremediation. 2007 Jul-Aug;9(4):257-68. doi: 10.1080/15226510701473476.
The agricultural soils near a copper smelter in southeast China were found to be highly contaminated with Cu, Pb, Zn, and Cd. Metal migration from the soil to groundwater presents an environmental risk that depends on the physicochemical properties of the contaminated soils. Soil solution samples were obtained using lysimeters from a loam soil with multiple metal pollutions over a period of about 1 yr. A field lysimeter study was also conducted to examine the potential use of (S, S')-ethylenediamine-N, N'-disuccinic acid trisodium salt (EDDSNa3) in chelate-enhanced phytoremedation and to evaluate the leaching of heavy metals. The average heavy metal concentrations in the soil solution (without the addition of EDDS) were high (e.g., 0.15 mg Pb L(-1) at a 50-cm depth) compared to the upper limit for protection of groundwater in China, but varied during the sampling period. Cu concentrations were not correlated with pH or dissolved organic carbon (DOC), but Zn and Cd concentrations were related to soil solution pH. EDDS enhanced metal solubility in the soil, but plant metal uptake by Elsholtzia splendens Nakai did not increase accordingly. There may be an increasing risk of groundwater pollution by Cu and the EDDS enhanced phytoremediation technique needs to be carefully applied to minimize this side effect.
中国东南部一家铜冶炼厂附近的农业土壤被发现受到铜、铅、锌和镉的高度污染。金属从土壤向地下水的迁移带来了环境风险，这取决于受污染土壤的物理化学性质。使用土壤渗漏采集器从一块受到多种金属污染的壤土中获取土壤溶液样本，采样期约为1年。还开展了一项田间土壤渗漏采集器研究，以考察（S，S'）-乙二胺-N，N'-二琥珀酸三钠盐（EDDSNa3）在螯合强化植物修复中的潜在用途，并评估重金属的淋溶情况。与中国地下水保护上限相比，土壤溶液（未添加EDDS）中的重金属平均浓度较高（例如，在50厘米深度处铅浓度为0.15毫克/升），但在采样期间有所变化。铜浓度与pH值或溶解有机碳（DOC）无关，但锌和镉浓度与土壤溶液pH值有关。EDDS提高了土壤中金属的溶解度，但海州香薷对金属的吸收量并未相应增加。铜污染地下水的风险可能会增加，需要谨慎应用EDDS强化植物修复技术以尽量减少这种副作用。
